09.02  Start-Up 
Siemens AG    6SE7087-6AK85-1AA0 
4-33 
Rectifier/Regenerating Unit    Operating Instructions 
Example 2: Available:  P075 (rated DC current) = 420 A 
 
Required:  Map the output current r035 between -630 and +630 A to -10.00 V to 
  +10.00 A at the analog output 
 
♦  Connect-up parameter r035 at the analog output: 
P655 "CUR-AA actual values“ = 035 
 
♦  Convert the required output range in [%]: 
r035 should be taken from the parameter list, Section 5: 
Analog output: 100% = P075 
 
Thus, the following is obtained for the range to be represented: 
-630 A → -150% (Parameter value PWE1)  represented as V
off1
 = -10.00 V 
+630 A → 150% (Parameter value PWE2)  represented as V
off2
 = +10.00 V 
 
♦  Define gain factor 
P656 and offset P657: 
 
The following is obtained from the formula shown above: 
 
[]
)
[] []
[]
[]
[]
[]
()
 V 0.00 V0.001 V10
% 100
% 150.00-  V 6.67
10V
% 100
%PWE Vfactor Gain
V U =V Offset
 V6.67
% 300
% 100 V20.00 
% 150% 150-
%100   V)10.00  V 10.00(
%PWE %PWE
%100 VU  VU
V factor ainG
 
 1  
off1
 
 2  1
   off2 off1
=+−=
⎟
⎠
⎞
⎜
⎝
⎛
×
−−=
⎟
⎠
⎞
⎜
⎝
⎛
×
−
=
−
×−
=
−
×−−
=
−
×−
=
 
 
  To be adjusted:  Gain 
P656 = +6,67 V 
  offset 
P657 = 0,00 V 
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